Device for removing and conveying injection-molded piece

ABSTRACT

A tranparent thin bottle-shaped container is produced by means of a technology for biaxial orientation blow molding a cylindrical piece with a bottom from polyethylene terephthalate material. The pieces are molded in large number in each injection molding process of an injection molding machine. The pieces thus formed immediately after the injection molding are held simultaneously in large number at the gates integrally projected therefrom by a base plate moved forward at the front of the mold in the injection molding machine. They are then conveyed to a gate cutting unit provided near the injection molding machine. The gates are cut from the pieces sequentially by the gate cutting unit and are conveyed onto a conveyor. The pieces are gradually cooled from the hot molded temperature during the conveyance and are additionally cooled while being conveyed on an oblique conveyor installed with a cooler to room temperature or lower predetermined temperature. The cooled pieces are then supplied to a heater immediately before entering a biaxial orientation blow molding process.

BACKGROUND OF THE INVENTION

This is a division of application Ser. No. 32,970 filed Apr. 24, 1979,now U.S. Pat. No. 4,514,166.

The present invention relates to a device for removing and conveying aninjection-molded piece in an apparatus for fabricating a bottle-shapedblow-molded container of a biaxially oriented plastic. Morespecifically, it relates to a piece process line which has the steps ofdrawing a preformed piece from the mold core of an injection moldingmachine, cutting the gates off of the pieces, and temporarily coolingthe pieces before heating them to a temperature adapted for a biaxialorientation process.

Polyethylene terephthalate resin has a wide range of applications in thefield of molding material into synthetic resin bottle-shaped containersbecause of its superior physical properties and characteristics.

In molding a bottle-shaped container of polyethlene terephthalate resin,there is adopted a so-called injection blow molding process in which apreformed piece of cylindrical shape with a bottom is injection-molded,and is then biaxially oriented blow-molded to produce preferablecharacteristics.

Therefore, such a bottle-shaped container is sequentially molded by aprocess having the steps of injection molding the piece, removing thepiece thus injection-molded, and clamping the piece in a blow moldingmachine for blow molding the same.

It is desired to automate all of these steps to complete the moldingprocess of such a bottle-shaped container. However, a considerably thickgate is integrally formed at the piece thus injection-molded owing topolyethylene terephthalate characteristics, and this gate of the pieceis manually separated with an exclusive cutter.

However, since each run of the injection molding process takes muchlonger than each run of the blow molding process and since theinjection-molded pieces are not as large, a number of such pieces areproduced each in molding process. Accordingly, it requires even longerto completely fabricate the bottle-shaped containers since the numerouspieces thus injection-molded must be independently manually separatedfrom their gates, resulting in remarkably inefficient productivity.

SUMMARY OF THE INVENTION

The present invention provides a device for removing and conveying aninjection-molded piece (preform) in an apparatus for fabricating abottle-shaped blow-molded container of a biaxially oriented plastic. Thedevice comprises a piece removing unit for holding the gates of numerouscylindrical pieces with bottoms molded by sequential injection moldingsteps in an injection molding machine and moving them away from themachine, a gate cutting unit for separating the gates of the pieces thusremoved, and a cooler for cooling the pieces to room temperature or lessthan room temperature as predetermined.

An object of the present invention is to provide a device for removingand conveying an injection-molded preform for a bottle-shapedblow-molded container of polyethylene terephthalate immediately afterthe molding process from an injection molding machine and to a biaxialorientation blow molding machine, which can simutaneously remove thepieces with bottoms from the molds of the injection molding machinewithout scratches.

Another object of the present invention is to provide a device forremoving and conveying an injection-molded preform for a bottle-shapedblow-molded container of polyethylene terephthalate immediately afterthe molding process from an injection molding machine and to a biaxialorientation blow molding machine which can hold numerous pieces thusinjection-molded via a base plate without altering their array and canrapidly convey them to a gate cutting unit.

Still another object of the present invention is to provide a device forremoving and conveying an injection-molded preform for a bottle-shapedblow-molded container of polyethylene terephthalate immediately afterthe molding process from an injection molding machine and to a biaxialorientation blow molding machine which can cool the pieces thusinjection-molded to a predetermined temperature during the piececonveying time in order to make uniform the heating conditions of thepieces immediately before the biaxial orientation blow molding process.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of the present invention willbecome apparent from the following description of the preferredembodiments of the present invention when reading with reference to theaccompanying drawings, in which:

FIG. 1 is a side view of a preferred embodiment of the device in anorientation blow molding process line including removal of piecespreformed in an injection molding machine according to the presentinvention;

FIG. 2 is a view showing the molding sequence of the pieces in theprocess line according to the present invention;

FIG. 3 is a partial front view of the device for removing the piecesfrom the injection molding machine according to the present invention;

FIG. 4 is a side view of the device shown in FIG. 3;

FIG. 5 is an expanded front view of the base plate of theinjection-molded piece removing unit in the device of the presentinvention;

FIG. 6 is a side view of the base plate shown in FIG. 5;

FIG. 7 is a sectional view of the unit shown as taken along the lineVII--VII in FIG. 5;

FIG. 8 is a sectional view of the base plate taken along the lineVIII--VIII in FIG. 6;

FIG. 9 is a side view of the gate cutting unit of a preferred embodimentof the present invention used for cutting the gate of the injectionmolded piece;

FIG. 10 is a front view of the gate cutting unit shown in FIG. 9;

FIG. 11 is a front view of a preferred embodiment of the injectionmolded piece intermittently lowering mechanism of the present inventionused for the gate cutting unit;

FIG. 12 is an enlarged plan view of the cutting portion in the gatecutting unit;

FIG. 13 is an enlarged front view of the cutting portion shown in FIG.12;

FIG. 14 is a sectional view of the cutting portion taken along the lineXIV--XIV in FIG. 13;

FIG. 15 is a sectional view of the cutting portion taken along the lineXV--XV in FIG. 13;

FIG. 16 is a longitudinal side sectional view of a preferred embodimentof the cooler of the present invention used for the device of thepresent invention; and

FIG. 17 is a sectional view of the cooler taken along the lineXVII--XVII in FIG. 16.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, particularly to FIG. 1 showing a sideview of the biaxial orientation blow molding process line employing theprinciple of the present invention, wherein like reference numeralsdesignate the same parts in the following views, an injection moldingmachine 10 has an injectin-molded piece removing unit 11, and a gatecutting unit 12 provided near the piece removing unit 11. A beltconveyor 13 and a cooler 14 follow the gate cutting unit 12. Next to thecooler 14 are sequentially disposed a conveyor 15, an aligning unit 16,and an orientation blow molding machine 17 including a heater (notshown).

The injection molding machine 10 molds numerous cylindrical pieces 18each with a bottom.

As shown in FIG. 2, each of the pieces 18 has a prefinished neck portion19 at the opening side thereof, and a gate 20 projected integrally fromthe center of the bottom thereof. The gate of the piece 18 is cut fromthe piece 18 by the gate cutting unit 12. The piece 18 is then fedthrough the sequential units described above, then to a jig, heated bythe heater (not shown) while being supported by the jig, then orientedlongitudinally in the orientation blow molding machine 17, furtheroriented laterally in the molding machine 17, and thus molded finally toa bottle-shaped container 21 of a biaxial orientation blow-moldedplastic as exemplified by the preferred embodiment according to thepresent invention shown at the rightmost part in FIG. 2.

Each of the respective units in the piece molding process lineconstructed according to the present invention will be described indetail.

Piece Removing Unit

FIGS. 3 through 8 show the detailed configuration of a preferredembodiment of the piece removing unit 11 according to the presentinvention. The piece removing unit 11 has a rail 22 fixedly installedperpendicularly over a mold 50 in the injection molding machine 10,moving means 23 laterally movable to the left or right along the rail22, and a base plate 24 elevationally movably hung from moving means 23integrally with a holding mechanism (not shown).

The base plate 24 is constructed to make a flat front plate 25 contact aflat rear plate 26 in a relatively slidable manner upon telescopicmovement of a hydraulic cylinder 27 with a piston rod 57. By thisconstruction, the base plate can hold or release the piece 18 to bemolded into a bottle-shaped container of polyethylene terephthalateresin at the gate 20 projected from the center of the bottom of thepiece 18 by means of the relative sliding movement between the front andrear plates. See FIG. 6.

The front plate 25 is disposed to face a male mold 51 (FIG. 3) opened atthe front surface in the injection molding machine 11 and is constructedto have a number of longitudinally elongated holes 28 perforated andarranged in the same manner and number as those of a number of cores 52projected from the mold 51 (FIG. 5). Each of the holes 28 has apredetermined length of the extent capable of receiving the gate 20 ofthe piece 18 at the bottom thereof. A number of bearers or supportmembers 29 protruded from the front surface of the front plate 25directly under the respective holes 28 to carry the respective pieces 18when the gates 20 enter the respective holes 28. Thus, each of thebearers 29 is projected at the position lower, by substantially a radiusof the piece 18, than the bottom of each of the holes 28.

In the preferred embodiment also shown in FIG. 7, the rear plate 26 isdisposed to make slidable contact with the front plate 25 at the backsurface thereof and is constructed to have a number of spill holes 31perforated and arranged correspondingly at the lower portions of therespective holes 28 of the front plate 25 in such a manner that each ofthe gates 20 of the pieces 18 may not collide at the top thereof withthe rear plate 26 when it enters each of the holes 28 so that each ofthe gates 20 may completely enter the hole 28 of the front plate 25.

A holder 32 is provided at the upper portion of each of the spill holes31 to be slidable in the hole 28 of the front plate 25. The holder 32makes at the front and rear surfaces thereof surface contacts with theinside surfaces of the front and rear plates 25 and 26, respectively, inslidable manner to be assembled tightly with the front and rear plates25 and 26.

As also shown in FIG. 7, the holder 32 has a compression spring 32afilled therein, a gate holding piece 32b telescopically slidablyinserted thereinto, a balance spring 32c filled in the gate holdingpiece 32b, a guide pin 32d slidably inserted through the holder 32 andpartly at the gate holding piece 32b, and a guide cylinder 32e forguiding the gate holding piece 32b slidably.

Referring back to FIGS. 5 and 6, a hydraulic cylinder 27 iselevationally telescopically secured to the rear plate 26 via a bracket33 fixedly secured to the back surface at the upper portion of the rearplate 26 in a manner slidable at a piston rod 34.

In FIG. 6, with reference to the detailed relationship between the rearplate 26 and the cylinder 27, a vertical pin 41 is secured to the sideof the cylinder 27 and is journaled with the bracket 33 in slidablemanner in such a manner that the cylinder 27 is relatively elevationallymovable with respect to the rear plate 26. Further referring to FIG. 8,a frame 42 is suspended from the bottom of the cylinder 27 and isconstructed to mount a pinion 43 at the lower portion therein. A rack 35staying in mesh with the pinion 43 is connected to the lower end of thepiston rod 34 telescoped with the cylinder 27, and is also secured atthe lower end thereof through a bracket 36 to the back surface at thelower portion of the rear plate 26. Thus, as the rear plate 26, bracket33, piston rod 34, rack 35, and bracket 36 are integrally assembled viathe pins or the like, the rear plate 26 can be elevationally moved withrespect to the cylinder 27 upon telescopic movements of the cylinder 27at the piston rod 34.

With reference back to FIG. 6, a rack 53 is disposed to face the rack 35connected to the piston rod 34, and is assembled to stay in mesh withthe pinion 43 slidably in the frame 42, and is further integrally fixedthrough a connecting pin 54 movably inserted into a longitudinallyelongated hole 37 perforated at the lower portion of the rear plate 26,to the front plate 25.

The base plate 24 is thus coupled with the moving means 23 as washeretofore described. As obviously understood also from FIG. 8, thepiston rod 34 is suspended from the cylinder 27 in the state as shown inFIGS. 8, 5, and 6. Accordingly, when the piston rod 34 is hydraulicallyretracted from the cylinder 27 upwardly, the pinion 43 staying in meshwith the rack 35 connected thereto turns as designated by an arrow inFIG. 6 to thus cause the rack 53 integral with the front plate 25 tomove downwardly as indicated by an arrow in FIG. 6. The front and rearplates 25 and 26 relatively slidably move by means of such operations ofthe piston rod 34 telescoped with the cylinder 27. Therefore, the hold37 of the rear plate 26 for movably receiving the pin 54 for connectingthe rack 53 to the front plate 25 must have the length of the extentthat the pin 54 may not be obstructed by the relative elevationalmovements of the front and rear plates 25 and 26.

In another respect of the relative elevational movements of the frontand rear plates 25 and 26, since the cylinder 27 is fixedly secured toan overhead moving mechanism 60 as will be hereinafter described in moredetail, the rear plate 26 moves upwardly with respect to the cylinder 27and the front plate 25 upon retraction of the piston rod 34 with thecylinder 27. In other words, the front plate 25 and the cylinder 27themselves do not move at all.

As a result of this relative movement of the front and rear plates 25and 26 of the base plate 24, when the gate 20 of the piece 18 isinserted into the gap between the lower end surface of the hole 28 ofthe front plate 25 and the bottom surface of the gate holding piece 32bof the holder 32 while the gap is sufficiently opened, namely the pistonrod 34 is upwardly retracted with the cylinder 27 and the piston rod 34is then extended downwardly from the cylinder 27, the rear plate 26 isrelatively elevationally upwardly and then downwardly moved with respectto the front plate 25 to thus cause the gate 20 of the piece 18 to beheld between the lower end surface of the hole 28 of the front plate 25and the bottom surface of the gate holding piece 32b of the holder 32.

The base plate 24 thus constructed and operated as was heretoforedescribed performs sufficiently its function as mounted to the movingmechanism 60 as briefly shown in FIGS. 3 and 4.

The rail 22 is moved over the injection molding machine 10 with theopened molds to a preferable position, i.e., a gate separator 70, in thenext step.

The moving means 23 moves along the rail 22 via a motor 55 mounted onthe moving means 23. A longitudinal cylinder 63 is horizontallyperpendicularly mounted to the moving means 23 with respect to the rail22. An elevational cylinder 64 is additionally attached vertically tothe front end of the piston rod 56 telescoped with the cylinder 63. Thecylinder 27 is connected at the upper end thereof to the lower end ofthe piston rod 57 telescoped with the cylinder 64, as clearly disclosedin FIG. 3.

Therefore, the base plate 24 can laterally move along the rail 22 viathe moving means 23, longitudinally move via the longitudinal cylinder63, and elevationally move via the elevational cylinder 64 in FIGS. 3and 4.

In operation of the device with the piece removing unit thus constructedaccording to the present invention, the base plate 24 is, for example,moved upwardly by the telescopic operation of the cylinder 64, isapproached to the moving means 23 by the operation of the cylinder 63,and is then disposed over the molds of the injection molding machine 10by the moving means 23.

In the meantime, the pieces 18 formed immediately after the molding areadhered to the corresponding cores 52 projected from the male mold 51opened in the injection molding machine 10. The cylinders 63 and 64 aretelescoped to face the front plate 25 at predetermined position with thesurface of the mold 51. The cylinder 63 is further operated to approachthe base plate 24 to the mold 51 in order that the gates 20 of therespective pieces 18 may enter corresponding holes 28 of the front plate25 as was previously described.

Then, the gates 20 of the respective pieces 18 are held respectivelybetween the holders 32 and the front plate 25 by the telescopicoperation of the cylinder 27. Then, the cylinder 63 is telescoped tohorizontally draw the pieces 18 from the respective cores 52 of the mold51. However, as a matter of course, since the pieces 18 are tightlyadhered to the respective cores 52 of the mold 51, it is apprehendedthat, if they are held between the holders 32 and the front plate 25 byelevationally moving the front plate 25, they may deform. Accordingly,only the rear plate 26 is constructed to elevationally move with respectto the front plate 25 relatively so that the holes 28 of the front plate25 disposed accurately with the respective pieces 18 as coupled with therespective cores 52 of the mold 51 may not displace.

After the pieces 18 are thus drawn from the mold by the base plate 24,the latter is raised by the cylinder 64, and is moved over the gateseparator 70 as exemplified to be faced with piece holders 71 of thepiece separator 70 by the telescopic operations of the cylinders 63 and64. Then, the gates 20 of the respective pieces 18 will be placed on therespective piece holders 71 and be cut as will be hereinafter describedin more detail.

Since the piece removing unit is thus constructed and operated, it canremove a number of the pieces 18 to be molded into bottle-shapedcontainers of polyethylene terephthalate resin immediately after themolding and convey them to the next process step without breakage of thearray from the injection molding. Since the piece removing unit furtherdraws the pieces from the respective cores of the mold while holding thegates of the respective pieces and conveys them as they are, it may notscratch any of the peices 18 which are feasibly subjected to scratchesas formed immediately after the molding.

Gate Cutting Unit

The gate cutting unit 12 constructed according to the present inventionis constituted to receive the pieces 18 integral with the respectivegates 20 from the injection molding machine 10 horizontally in the samearray as that at the injection molding time, intermittently convey anumber of the pieces to the next process step until the next pieces 18are injection-molded by the injection molding machine 10, and cut thegates 20 of the respective pieces 20 during the stoppage of theintermittent conveyance of the pieces 20.

The gate cutting unit 12 has a piece conveyor 72 for intermittentlymoving the respective piece holders 71 for horizontally receiving anumber of the pieces 18 of the same array as that at the injectionmolding time, at predetermined distance and speed, and a gate cutter 74for cutting the gates 20 of the respective pieces 18 conveyed to thecutting position by the piece conveyor 72 during the stopping period ofthe piece holders 71.

The components of the piece cutting unit 12 will be described further indetail.

Piece Conveyor 72

FIGS. 9, 10, 11 and 13 show a preferred embodiment of the piece conveyor72 of the piece cutting unit 12 according to the present invention,which is operated to draw a number of the pieces from the injectionmolding machine, and, more particularly, to draw horizontally the pieces18 (16 pieces as exemplified in the Figures) in the same array as thatat the injection moldling time and sequentially convey the pieces 18 (4pieces as exemplified in this embodiment) to the cutting positionintermittently until the next pieces are completely molded in theinjection molding machine.

In the preferred embodiment of the piece conveyor 72 as shown, the piececonveyor 72 assembles the piece holders 71 for horizontally holding thepieces 18 at predetermined interval with each of chains 91 installedvertically respectively between drive sprockets 88 and guide sprocket 90mounted on a base 73, and arranges a required number of a set of thedrive and guide sprockets 88 and 90, chain 91 and piece holders 71 inparallel.

The piece holders 71 are arranged entirely in the same array as that ofthe cores 52 of the mold 51 in the injection molding machine 10 at thechain 91 in order to draw the injection-molded pieces 18 and to conveythem in the same array onto the piece holders 71 as that at theinjection molding time.

Each of the chains 91 (4 chains as exemplified in the embodiment) ofpredetermined number for assembling the piece holders 71 atpredetermined intervals is vertically engaged between the drive sprocket88 installed on the base 73 and the guide sprocket 90 installed at amounting frame 89 stood on the base 73 directly above the sprocket 88.

Each of the drive sprockets 88 is fixedly secured to a drive shaft 86rotatably secured via a bearing 87 onto the base 73, and is driventhrough a reduction gear 80, torque limiter 81, index unit 82, outputgear 83, and transmission gear 84 via a drive gear 85 secured to one endof the drive shaft 86 from a prime mover, as specifically illustrated inFIG. 9.

Although the rotating force of the prime mover is continuous constantspeed in this case, it is converted to an intermittent rotatingoperation of predetermined duration through the index unit 82 and isthus transmitted to the drive shaft 86.

The rotating amount of the drive shaft 86 as intermittently transmittedin each intermittent rotation is so set that the chain 91 engagedbetween the sprockets 88 and 90 moves in the distance equal to that ofthe piece holder 71 mounted at the chain 91.

Accordingly, each of the piece holders 71 will stop always at apredetermined position where the previous piece holer 71 was stopped bythe intermittent movement, that is, the respective piece holders 71 willsequentially stop at predetermined stopping positions in order. In otherwords, all the piece holders 71 may always stop entirely at the samearray and interval as those of the pieces 18 drawn from the mold 51 inthe injection molding machine 10.

A stopper plate 93 is fixedly disposed for setting the backward movinglimit of the held pieces, at the back of the piece holders 71 disposedat the side for receiving the pieces 18, at the front side of the pieceholders 71 mounted at the chains 91 vertically engaged over between thesprockets 88 and 90, and particularly at the back of the piece holders71 disposed at the cutting position.

The stopper plate 93 is constructed and installed to prevent the pieces18 supplied onto the piece holders 71 from backwardly displacing to dropby the vibration caused by the movement of the piece holders 71 and torestrict the pieces 18 at the cutting position. More particularly, whenthe pieces 18 are inserted into piece head inserting recesses 113 of thegate cutting unit 12 at the cutting position as will be hereinafterdescribed in more detail, they may not largely move backwardly on thepiece holders 71 by the inserting force.

Gate Cutter 74

In the preferred embodiment shown in FIGS. 9 through 15, when thelowermost piece holder 71 of the holders 71 receiving the pieces 18drawn in the same attitude and array as those at the molding time fromthe injection molding machine 10 via the piece removing unit 11 reachesits cutting position as downwardly moved by one intermittent movementafter the reception of the pieces 18, the gate cutter 74 is operated tocut the gates 20 of the pieces 18 held by the piece holders 71 stoppedat the cutting position during the stopping period of the piece holders71 to separate the gate 20 from the piece 18.

A slide base 102 is slidably assembled along a guide rail 103 securedvia a bracket 104 to the base 73 horizontally along the axes of thepieces 18 held by the respective piece holders 71 at the front(rightwardly in FIG. 9) of the mounted piece holders 71 over the base73. That is, the slide base 102, is mounted longitudinally movably backand forth toward the pieces 18 held by the piece holders 71.

The piston rod telescoped with a cylinder 100 fixedly secured to abracket 101 fixed onto the upper front end (the rightmost end in FIG. 9)of the base 73 is connected to the slide base 102 to slidably move theslide base 102 along the guide rail 103 by the telescopic movements ofthe piston rod telescoped with the cylinder 100.

A piece head holder 111 is secured via mounting plates 114 and 115 ontothe upper surface of the slide base 102 to face the piece 18 disposed atits cutting position at the front. In the preferred embodimentparticularly shown in FIG. 15, the piece head holder 111 has a centerhole opened to allow only the gate 20 of the piece 18 at the bottom ofshort cylindrical shape column to protrude therethrough and to maketight contact with the head (bottom) of the piece 18.

A cushion member 112 is fixedly inserted into the piece head holder 111to hold the piece 18 to be inserted into the piece head holder 111without any scratch or fluctuation. Thus, a piece head inserting recess113 is formed by the cushion member 112 and piece head holder fixturewithin the piece head holder 111.

As more specifically exemplified in FIG. 10, a cutter cylinder 105 issecured fixedly to one side end (the leftmost end as shown) of the uppersurface of the slide base 102 by a mounting fixture 106 separately fromthe piece head holder 111. A rectilinear square-cross sectional bar-likeslide bar 108 is connected at the end thereof to the end of the pistonrod telescoped with the cylinder 105. This slide bar 108 is so assembledby a guide bracket 107 fixedly secured onto the upper surface of theslide base 102 as to be movable in the horizontal directionperpendicular to the axes of the pieces 18 held by the piece holders 71,i.e., along the axes of the slide bar 108.

A cutter 110 is secured via a mounting fixture 109 to the slide bar 108at the position facing the piece head holder 111 in a manner makingclose contact with the front surface of the piece head holder fixture atthe cutting edge thereof. The cutter 110 makes at one surface thereofincluding the cutting edge contact with the front surface of the piecehead holder 111 to slidably move the front surface of the piece headholder 111 by the movement of the slide bar 108 upon telescopicoperation of the cutter cylinder 105.

In operation of the gate cutter 74 thus constructed according to thepresent invention, when the pieces 18 are drawn from the injectionmolding machine 10, are conveyed to the piece holder 71 in the attitudethat the gates 20 integral therewith are directed forwardly by the pieceremoving unit 11, and then the piece removing unit 11 is retracted fromthe pieces 18, the respective piece holders 71 are intermittently movedto cause the lowermost holder 71 for holding the piece 18 to be stoppedat the cutting position. When the piece holder 71 is thus stopped at thecutting position, the cylinder 100 is telescoped to move forwrad theslide base 102 along the guide rail 103 to urge the head of the piece 18disposed at the cutting position tightly within the piece head insertingrecess 113. Since the piece 18 thus held on the piece holder 71 makescontact at the rear end thereof with the stopper plate 93 as waspreviously described, it is tightly inserted at the head thereof intothe piece head inserting recess 113 by the forward movement of the slidebase 102.

When the slide base 102 is moved forwardly so that the piece 18 isinserted at the head thereof tightly into the piece head insertingrecess 113, the cutter cylinder 105 is telescoped to move forwardly theslide bar 108 as in rightward direction in FIGS. 12 and 13 to thus causethe cutter 110 moving integrally with the slide bar 108 to separate thegate 20 projected from the front surface of the piece head holder 111from the piece 18.

When the cutter 110 completely cuts to separate the gate 20 from thepiece 18, the slide bar 108 is backwardly returned integrally with thecutter 110 in a manner of reverse operation of the cutter cylinder 105to the above. Then the cylinder 100 is reversely telescoped to move theslide base 102 back to the original position.

It is noted that the respective movements of the slide base 102 from theforward movement to the backward movement must be executed during thestopping period of the piece holders 71 in intermittent operation.

The pieces 18 supplied by one operation of the piece removing unit 11are sequentially cut at the gates 20 thereof as described above. It isalso noted that all such pieces 18 must be completely separated from thegates 20 thereof until the pieces 18 formed in the next injectionmolding process are then supplied thereto.

In the meantime, the piece holders 71 must be stopped when they receivethe pieces 18 from the piece removing unit 11. Since the time from whenthe pieces 18 are inserted into the respective piece holders 71 by thepiece removing unit 11 to when the piece removing unit 11 is backwardlyreturned is longer than the stopping time of the intermittent operationrequired to sequentially cut the gates 20 from the pieces 18 ofpredetermined number as supplied, it must stop the intermittentoperation of the piece holders 71 for predetermined time when the pieces18 are conveyed from the piece removing unit 11 to the piece holders 71.

There may variously be considered means for stopping the intermitentoperation of the piece holders 71 for this predetermined time. The mostsimple means, for example, has preferably an electromagnetic clutchinstalled at the torque limiter 81 in the piece conveyor 72, and a limitswitch for controlling the clutch to detect the operation of the pieceremoving unit 11.

The pieces 18 thus separated from their gates 20 are lowered while beingheld by the piece holders 71 by the intermittent movement of the pieceholders 71, and are then dropped on the belt conveyor 13 from the pieceholders 71 when the piece holders 71 are tilted and reversely turned atthe drive sprocket 88 to be then conveyed to the next cooler via theconveyor 13.

Cooler

FIGS. 16 and 17 show a preferred embodiment of the cooler 14 accordingto the present invention. The pieces 18 separated from their gates 20 bythe gate cutting unit 12 are conveyed to the cooler 14 via the beltconveyor 13 as described previously.

Reference numeral 120 illustrates a conveyor obliquely installed towardthe forward direction via a flat plate 142 at the end of the conveyor13. This conveyor 120 is constructed to have an endless belt 122 engagedbetween pulleys 121 and 121 provided at both ends, which belt 122, asexemplified in FIGS. 16 and 17, has lateral projection straps 123 formedat equal intervals on the outer surface thereof to convey the pieces 18from the lower position to the higher position engaged with the straps123 by the circulation of the belt 122.

124 represents a supporting plate for preventing the belt 122 fromdeflecting.

130 illustrates a cover for enclosing the belt conveyor 120, which cover130 has a cooling air inlet 132 formed at the center of the top plate131 thereof.

The cooling air is fed into the cover 130 to cool the hot pieces 18formed immediately after the injection molding process to apredetermined lower temperature thereby to prepare the pieces 18 underthe optimum conditions for the biaxial orientation blow molding of thenext step at a uniform heating time. It is, therefore, noted that, sincethe pieces 18 cannot be abruptly cooled when they are cooled to roomtemperature or lower predetermined temperature in the step of conveyingthe pieces 18 via the conveyor 120, the cooling air must be scatteredwithin the cover 130 so as to gradually cool the conveyed pieces 18.

Therefore, a number of vent holes 133 are perforated at a scatteringplate 134, which is installed a suitable distance from the top plate 131of the cover 130 within the cover 130 to widely distribute the coolingair from the inlet 132 via the vent holes 133.

Since it is apprehended that the cooling air will not be sufficientlyscattered if the holes 133 are perforated directly under the inlet 132at the scattering plate 134, the holes 132 are so perforated as to avoidthat portion directly under the inlet 132 of the scattering plate 134 todistribute the air more completely.

Reference numeral 143 depicts a conveyor for feeding the pieces 18conveyed to the higher position further to the next step.

According to the present invention, as fully described hereinbefore,since the device for removing and conveying the pieces can draw theinjection-molded pieces in the injection molding machine and convey themto the gate cutting unit without scratch to automatically cut the gatesfrom the pieces, it can shorten the time required to cut the gates fromthe pieces, eliminate the manual power entirely, largely reduce themolding time to complete the bottle-shaped containers of biaxialorientation blow-molded polyethylene terephthalate resin, enableautomation of the respective molding works to complete the bottle-shapedcontainers, and perform without troubles with relatively simpleconstruction and operation. Furthermore, since the device of the presentinvention can exactly convey the pieces formed immediately after theinjection molding process without any scratch and can cool the piecesthus conveyed to the optimum predetermined temperature for the heatingstep immediately before the biaxial orientation blow molding process, itcan prepare the pieces to be under the optimum conditions for the nextmolding process step.

Although specific embodiments of the present invention have beendescribed hereinbefore, it should be understood that numerous variationsthereof may be employed without departing from the invention, and it isreiterated that the examples given as above are simply illustrative ofthe device for removing and conveying the pieces.

What is claimed is:
 1. A gate cutting device for receiving piecesintegral with the gates from an injection molding machine horizontallyin the same array as that of the injection molding machine,intermittently conveying the pieces, and cutting sequentially the gatesfrom heads of the pieces, said device comprising:piece conveying meanscomprising:a number of piece holders intermittently movable at apredetermined moving interval for horizontally holding the pieces at avertical interval corresponding to the intermittent movement interval ofsaid piece holders, and a stopper plate disposed adjacent the pieceholders for restricting movement of the pieces held by the piece holderaway from a cutting position for cutting the gates from the pieces; andgate cutting means comprising:piece head holders each comprising an endwall having a piece head inserting recess formed therein for receivingthe head of a piece disposed at the cutting position and an openingformed therein through which said gates can project when held in saidpiece head holders, said piece head holders being longitudinally movableback and forth toward the pieces held by the piece holders at thecutting position, and a cutter for cutting the gates projected from thepiece head holders, said cutter comprising at least one blade mountedadjacent said wall movably in a direction perpendicular to the axes ofthe pieces held by the piece holders.
 2. A gate removing device forseparating gates from injection molded cylindrical preforms havingclosed heads with gates projecting therefrom, said devicescomprising:preform holders for holding said preforms horizontally withsaid gates projecting horizontally axially therefrom; and gate cuttingmeans horizontally movable toward and away from said preform holders ina direction parallel to the axes of said preforms, and adapted tocontact said heads of said preforms at a gate cutting position, saidgate cutting means comprising head inserting recesses for receiving saidheads when said gate cutting means contacts said heads at said gatecutting position, each said recess having an end wall with an openingtherethrough for receiving one of said gates, and a cutter for cuttingsaid gates from said preforms at said gate cutting position, said cutterbeing movable along said end walls to cut said gates from said preforms.3. A device according to claim 2, further comprising stopper means forrestricting movement of said preforms at said gate cutting position. 4.A device according to claim 3, wherein said stopper means comprises astopper plate.
 5. A device according to claim 2, wherein said cuttercomprises a horizontally movable slide bar, and said slide bar comprisesa number of cutting edges adjacent said end walls of said recesses.
 6. Adevice according to claim 2, wherein said preform holders areintermittently movable from a loading position to said gate cuttingposition.
 7. A device according to claim 6, comprising a holder conveyorfor intermittently vertically moving said preform holders from saidloading position to said gate cutting position.
 8. A device according toclaim 7, wherein said holder conveyor comprises an endless chain.
 9. Adevice according to claim 7, wherein said preform holders are verticallyspaced apart on said holder conveyor by a distance equal to a distanceof one intermittent movement of said preform holders.
 10. A deviceaccording to claim 7, further comprising stopper means for restrictingmovement of said preforms when said preforms are at said gate cuttingposition.
 11. A device according to claim 10, wherein said stopper meanscomprises a stopper plate.
 12. A device according to claim 7,wherein:said gate cutting means further comprises head insertingrecesses for receiving said heads when said gate cutting means contactssaid heads at said gate cutting position, each said recess having an endwall with an opening therethrough for receiving one of said gates; andsaid cutter is movable along said end walls to cut said gates from saidpreforms.